21210211022121 has 24 divisors (see below), whose sum is σ = 33920988782304. Its totient is φ = 12662812546560.

The previous prime is 21210211022107. The next prime is 21210211022123. The reversal of 21210211022121 is 12122011201212.

21210211022121 is a `hidden beast` number, since 2 + 1 + 210 + 211 + 0 + 221 + 21 = 666.

It is not a de Polignac number, because 21210211022121 - 2²³ = 21210202633513 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21210211022094 and 21210211022103.

It is not an unprimeable number, because it can be changed into a prime (21210211022123) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 1598833336 + ... + 1598846601.

It is an arithmetic number, because the mean of its divisors is an integer number (1413374532596).

Almost surely, 2^{21210211022121} is an apocalyptic number.

It is an amenable number.

21210211022121 is a deficient number, since it is larger than the sum of its proper divisors (12710777760183).

21210211022121 is a wasteful number, since it uses less digits than its factorization.

21210211022121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3197680021 (or 3197680018 counting only the distinct ones).

The product of its (nonzero) digits is 64, while the sum is 18.

Adding to 21210211022121 its reverse (12122011201212), we get a palindrome (33332222223333).

The spelling of 21210211022121 in words is "twenty-one trillion, two hundred ten billion, two hundred eleven million, twenty-two thousand, one hundred twenty-one".